1. Field of the Invention
The present invention relates to improved polyarylene ester blends (hereinafter, referred to as "APC-blends") and to a method for enabling shaped articles prepared from APC-blends to be treated with hot water or steam without loss of the transparency thereof.
2. Description of the Prior Art
It is known that APC-blends, one component of which is a polyarylene ester (hereinafter, referred to as "APC") and another component of which is an other thermoplastic resin such as polyalkylene terephthalate or polycarbonate, have various advantageous properties compared with each of the components and other thermoplastic resin blends. APC-blends are successfully processed into various shaped articles, which have various advantages over shaped articles prepared from the APC alone or other thermoplastic resin. (cf. British Pat. No. 1,002,545, U.S. Pat. No. 3,792,115 and U.S. Pat. No. 3,792,118). One of the desirable properties of the shaped articles prepared from APC-blends is the excellent transparency. However, it has been found that the shaped articles prepared from APC-blends lose their transparency and become opaque when treated under conditions of a high temperature and a high moisture, particularly with steam. Therefore, APC-blends can not be used for the preparation of shaped articles which are required to retain the transparency thereof even when treated with hot water or steam.
This disadvantage of APC-blends is a serious problem in the preparation of shaped articles, particularly in the preparation of medical instruments such as containers for eye medicine or transfusion, because such medical instruments are sterilized with steam or boiling water and are required to be transparent.